Cardiovascular Surgery

Question 1

What pharmacologic class does milrinone belong to?

Answer 1

Inotropic agent; phosphodiesterase-3 inhibitor (it has been called an inodilator because it increases myocardial contractility AND promotes vasodilation)
(Lexicomp handbook, p. 1402)

Question 2

What is milrinone indicated for?

Answer 2

Short-term IV therapy of acutely decompensated heart failure

Lexicomp handbook, p. 1402

Question 3

What is the onset of milrinone?

Half-life elimination?

Answer 3

IV: 5 - 15 minutes
Normal renal function: about 2.5 hrs
(Lexicomp handbook, p. 1403)

Question 4

What is the mechanism of action of milrinone?

Answer 4

It increases contractility by allowing accumulation of cAMP secondary to inhibition of phosphodiesterase type 3 (PDE3), an enzyme that degrades cAMP.
(Lehne’s pharmacology, p, 523)

Question 5

What is the initial dose and maintenance infusion of milrinone?

Answer 5

25 - 75 mcg/kg over 10 - 20 min.
Infusion is 0.375 - 0.75 mcg/kg/min
(Lehne’s pharmacology, p, 523)

Question 6

What are the 4 features of tetralogy of fallot?

Answer 6

1. ventricular septal defect
2. overriding aorta
3. obstruction of the right ventricular outflow tract (usually pulmonary stenosis)
4. right ventricular hypertrophy (secondary to #3)

Question 7

What is a Blalock-Taussig shunt (classic)?

The most common type of shunt performed in the current era is a modified Blalock-Taussig shunt, which uses…

Answer 7

The original classic Blalock-Taussig shunt was performed by dividing the subclavian artery and creating an end-to-side anastomosis of the proximal subclavian artery stump to the ipsilateral pulmonary artery.

….a Gore-Tex interposition graft between the innominate or subclavian artery and pulmonary artery without dividing the distal subclavian artery.